Hello Hamza,
Try the following code snippet to close the RadWindow. You need to inject the javascript function to the asp label as it's text
and write the client side code to close the RadWindow as shown below in
order to close the RadWindow.
JS:
ASPX:
C#:
To remove border from RadWindow you can take a look into the following forum thread which discussed the same.
Remove the window border
Window without border
Thanks,
Princy.